The world is complex and full of possibilities. A logical argument doesn’t need to prove that something will happen exactly as described; it needs to show that one outcome is more likely than another. However, not all justifications are logical. When an argument feels weak or confusing, a reasoning fallacy has often crept in. These are common ways people unintentionally go wrong in their logic.

The following four tips will help you avoid common reasoning fallacies and respond more effectively when you encounter them in discussion.

1. Know the most common reasoning fallacies

The less energy you need to spend figuring out whether something is a fallacy, the more easily you will notice faulty reasoning both in your own thinking and in others’. The best way to avoid flawed logic is to be familiar in advance with what common reasoning fallacies look like.

In 2015, SpeakSmart trainer Anna Karolin wrote an article for Postimees outlining several common fallacies and briefly explaining why they represent poor reasoning. English-language materials introducing common reasoning fallacies are also widely available online by searching for the term logical fallacies.

2. Ask why and how a claim could be logical

If you don’t yet have a clear overview of common fallacies, there’s no reason to be discouraged. Often we sense that something is wrong with an argument even if we can’t immediately name the problem.

In such situations, two simple questions can help. First: why might this position be justified? In other words, what assumptions would need to be true for the claim to be logical? Second: how might this position be justified? What would a logical chain of reasoning look like, moving from reasonable assumptions to the conclusion?

If you struggle to answer either question, it is usually a strong indication that the reasoning does not hold up.

3. Notice attempts to influence you with flawed reasoning

Reasoning fallacies are also known as demagogical techniques. This term is commonly used to describe deliberately flawed reasoning, often employed by politicians. There is a simple explanation for this: many fallacies create the impression of logical reasoning while actually appealing to the speaker’s authority or the audience’s emotions.

Appealing to reputation or emotions is often more effective than relying on pure logic. Unfortunately, such manipulation has little real argumentative value, and people who accept these arguments in good faith may later discover that what initially seemed convincing was ultimately empty.

In essence, demagoguery does not differ from reasoning fallacies. To avoid falling into this trap, consider whether a claim provokes strong emotions in you, or whether you are inclined to accept or dismiss it solely based on who is presenting it. If the answer to either question is yes, it is worth investing a bit of extra effort to determine whether the reasoning is actually logical.

4. Assume good intentions

Effective argumentation requires at least two people. A logical error doesn’t automatically mean the other person is acting in bad faith or that their entire viewpoint is worthless. Focusing only on mistakes can shut down productive dialogue.

Focusing solely on another person’s mistakes can easily lead to conflict, where rational, constructive discussion becomes impossible. A more productive approach is to assume that there is something valuable in the other person’s thinking. If a flaw can be corrected without undermining the overall position, address it first and only then evaluate whether the argument itself is convincing.

Even when you disagree with the other person’s opinion, it is worth listening carefully and trying to understand why they hold that view. People are generally more willing to listen when they feel their perspective has already been heard.

We also tend to think things through more completely in our minds than we express them out loud. What feels obvious to us may not be obvious to others. At times, the logic is present but left unspoken. In such cases, it is important to recognize this possibility and allow the original speaker to fill in the gaps, rather than doing so on their behalf and potentially misinterpreting their reasoning.

Although logically justifying one’s views can sometimes feel demanding or tedious, a well-reasoned argument is often more persuasive and stronger than one based solely on factual evidence. In most cases, ensuring sound logic simply means avoiding common mistakes. By following these four simple principles, you can better evaluate both your own reasoning and that of others, leading to clearer thinking and more thoughtful, well-argued decisions.

Oskar Samuel Rebane
Trainer and Moderator
SpeakSmart

SpeakSmart is Estonia’s leading training and consultancy company in argumentative communication. Its mission is to help individuals and teams communicate effectively, think critically, express their viewpoints clearly, and make better decisions. Over 18 years of activity, the company has trained more than 22,000 people.